20545087 has 4 divisors (see below), whose sum is σ = 20610216. Its totient is φ = 20479960.

The previous prime is 20545051. The next prime is 20545097. The reversal of 20545087 is 78054502.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20545087 - 2¹⁹ = 20020799 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20545037) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32089 + ... + 32722.

It is an arithmetic number, because the mean of its divisors is an integer number (5152554).

Almost surely, 2^20545087 is an apocalyptic number.

20545087 is a deficient number, since it is larger than the sum of its proper divisors (65129).

20545087 is an equidigital number, since it uses as much as digits as its factorization.

20545087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65128.

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 20545087 is about 4532.6688606162. The cubic root of 20545087 is about 273.8856814383.

Adding to 20545087 its reverse (78054502), we get a palindrome (98599589).

The spelling of 20545087 in words is "twenty million, five hundred forty-five thousand, eighty-seven".